Sometimes, I get recordings of games that are "Not Recorded" for an "unknown reason" (as the History shows), but only autorecorded on channels 700+, as opposed to manually set for channels in the 600 range

Yesterday, I watched part of a game live, but today when I went to view the recording of it, it was "Not Recorded"

What it looks like: I'll see a show in the Now Playing List, and it will show it as having recorded "Partial", and only for the amount of time for the buffer I added at the end. So, for example, I had a game autorecorded for 6 hours with a 1.5 hour buffer at the end, and when I view it, it starts playing back at 6:00 and then shows 1.5 hours of the DirecTV logo with music in the background.

The Recording History shows "This program was not recorded because of an unknown reason. If you continue to encounter this problem, try restarting the DIRECTV-TiVo DVR." I have tried restarting the DVR -- no change.

The baffling thing: I can always see the broadcasts live. I can flip through the channels and, so long as a game is on that channel, I see the game live. Also, I have only seen this happen when I autorecord, and it picks a channel in the 700s. If I specifically choose a program in the 600s (the main RSN channel that is mapped to the 700s), I never have the blank recording.

The DirecTV Support folks ran through all sorts of tests and couldn't come up with anything. They only think that they should send me a service call (and for me to pay $49 for the service call), which might only result in the guy switching out my receiver, which may not fix the issue anyway.